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what do red lights on police cars mean?

what do red lights on police cars mean?

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Discussion

dpbird90

Original Poster:

5,386 posts

97 months

Tuesday 15th March 2011
quotequote all
just on the way home, saw a marked police car pulled someone over, but instead of blue lights the ones on the roof were flashing red. is there any difference between this and one with blue lights on top? sorry for any bad punctuation, i am typing this on my crappy motorola!

Haytch

168 posts

67 months

Tuesday 15th March 2011
quotequote all
The other day I saw a police car stopped with flashing reds instead of blues too, not sure why the need to switch them to blue though...

EDLT

14,795 posts

113 months

Tuesday 15th March 2011
quotequote all
Its more eye-catching I guess. It might stop mongs from standing on the brakes whenever they see blue lights.

Shmee

6,222 posts

120 months

Wednesday 16th March 2011
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Red from behind when stopped, blue from in front.

Cock Womble 7

29,908 posts

137 months

Wednesday 16th March 2011
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Shmee said:
Red from behind when stopped
I often see police cars sat (alone) on the hard shoulder or slip road with the rear red lights flashing and wondered what (if anything) this "means".

Is it just a simple "I am here" - are the red lights just additional to the hazards, or are we supposed to act on this display somehow?

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MGZRod

6,682 posts

83 months

Wednesday 16th March 2011
quotequote all
I see this quite a lot. I assume it's to tell which direction the car is facing, so you can prepare to maneuvre (or not if you see red!)

I.e If you see blue & red lights when you glance at mirror, no need to move to side of road.
Or if you see it ahead parked up, you may need to move over to avoid it (pulled someone over etc)

parapaul

2,828 posts

105 months

Wednesday 16th March 2011
quotequote all
It's something along these lines:

Blue flashing lights are very eye catching, and it's an inbuilt reaction for most drivers to either have a look, slow down, or do something else that would otherwise distract them from the rest of their drive.

When plod are stopped, particularly on the hard shoulder, they use the flashing rear reds as a warning to approaching traffic of the hazard they are creating or dealing with, without offering any more distraction than necessary to oncoming traffic.

Funk

17,735 posts

116 months

Wednesday 16th March 2011
quotequote all
Red is also at the long end of the light spectrum and therefore more easily seen at a distance by the human eye. This is why traffic lights are red for stop, as well as brake lights and tail lights. smile

Baryonyx

13,829 posts

66 months

Wednesday 16th March 2011
quotequote all
Yes, rear reds are used when stopped facing in the same direction as the movement of traffic on the carriageway, for instance if you pull someone over for using their phone etc etc. That said, cars parked across roads for traffic management (at a crash, for instance) will use their blues still. The rear reds are just a very noticeable hazard light.

There is usually a separate control on the panel for "rear reds" and a "runlock" control for when you're going to need blue lights on a stationary vehicle.

Gwagon111

4,422 posts

68 months

Wednesday 16th March 2011
quotequote all
Funk said:
Red is also at the long end of the light spectrum and therefore more easily seen at a distance by the human eye. This is why traffic lights are red for stop, as well as brake lights and tail lights. smile
yes Yellow is the colour that human eyes are most sensitive to.

Vipers

22,732 posts

135 months

Wednesday 16th March 2011
quotequote all
I seem to recall seeing this in London a couple of years ago, asked a couple of lovely lady bobbies, they told me they were the armed brigade?

Mind you, could only be within London itself, or things have changed.




smile

deveng

3,621 posts

87 months

Wednesday 16th March 2011
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Before reading the OP I wanted to be a smart arse and say "it's braking" based on the title.

insanojackson

3,890 posts

151 months

Wednesday 16th March 2011
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its simply an additional warning to stop inatentive drivers from rear ending you whilst stopped.